Anastasia Steele, half of the hot couple in E L James’s runaway erotic bestseller Fifty Shades of Grey, bites her lip a lot. The habit may remind a lot of readers of what some call the Kristen Stewart Lip Bite, so much a part of the character of Bella Swan in the movie adaptations of the Twilight saga. Coincidence? James, who gave her first American interview exclusively to Entertainment Weekly, describes herself as a Twihard who began her mid-life literary career after devouring Stephenie Meyer’s Twilight trilogy. The married mother of two teenage sons posted an early version of the current novel on a Twilight fan fiction website under the title Master of the Universe; at the time, she says, she still called her characters Bella and Edward. “You’ll find a lot of erotic stories about Edward on [those sites],” she says.

So is Ana’s mannerism left over from Fifty’s first online incarnation?

“If you think about what’s erotic about someone’s mouth, it’s either the lips or biting. That’s what you have to work with, what drives men wild,” says James, who also reports some interesting fan mail from her readers. “I had a lady write me recently who said that her husband kissed the book!” she says – testament to Fifty’s ability to rev up marital engines.